Although the cause of chronic fatigue is unknown, infection, hormone levels, and stress are also believed to play a role in its symptoms. Chronic fatigue often results from:
- Sleep disturbance in combination with chronic pain and depression
- Physical inactivity
- Poor diet
- Social and cultural factors
- Certain medical conditions (see below).
Regardless of the cause, chronic fatigue has a major impact on day-to-day functioning and quality of life.
(Click Chronic Fatigue Causes for more information.)
Chronic fatigue is a symptom of many diseases. Common conditions that can cause chronic fatigue include:
- Myalgic encephalomyelitis
- Multiple sclerosis
- Systemic lupus erythematosus (SLE or lupus)
- Multiple chemical sensitivities
- Sleep apnea
- Major depressive disorders
- Chronic mononucleosis
- Bipolar affective disorders
- Eating disorders (anorexia or bulimia)
- Autoimmune disease
- Hormonal disorders
- Subacute infections
- Alcohol or substance abuse
- Reactions to prescribed medications.
If a patient receives a diagnosis of any of these conditions, they would be excluded from having chronic fatigue syndrome unless their condition has been treated sufficiently and no longer explains their fatigue and other symptoms.